This invention relates generally to supplemental inflatable restraint systems often referred to as airbag systems. More particularly, this invention relates to a trim panel such as an instrument panel, having an integral door cover for concealing the airbag system in a vehicle passenger compartment.
U.S. Pat. No. 5,131,678 granted to John A. Gardner, Richard D. Rhodes, Jr. and Everett Hastings Jul. 21, 1992 discloses an air bag door cover that is an integral part of a decorative panel for a steering wheel. The panel comprises an aluminum backing plate, an outer flexible vinyl skin arid an intermediate elastomeric urethane foam layer. The vinyl skin is cast with a rectangular groove that defines a door. The cast vinyl skin is then placed in a mold in a spaced relationship with the backing plate after which the intermediate layer is foamed in place. The bottom of the rectangular groove is then cut at least part way through on three sides to provide a weakened section in the panel that includes an U-shaped cut line in the backing plate.
While the decorative panel of the above patent is well suited for its intended purpose, it has a drawback in that the bottom of the groove is cut at least part way through on three sides after the vinyl skin is cast and assembled into the decorative panel. This cutting in turn requires deep and narrow grooves to hide the cut. These grooves limit aesthetic design choices and may be difficult to form.
The object of this invention is to provide a trim panel that has an integral door cover for an airbag system that does not require cutting the bottom of the grooves.
Another object of this invention is to provide a trim panel that has a shaped plastic skin that includes a flap for an integral door cover for a SIR system that is partially outlined by a groove that does not require any cutting after the skin is cast to provide a weakened tear seam.
Still another object of this invention is to provide a trim panel that has an integral door cover for an airbag system that includes a shaped plastic skin having a flap partially outlined by a groove that is cast in an aesthetically pleasing manner to include a weakened tear seam at its bottom that does not require any cutting after the skin is cast.
Still yet another object of this invention is to provide a method for making such a trim panel and a mold for use in practicing the method.
A feature and advantage of the trim panel of this invention is that the trim panel has a cast plastic skin which includes a flap for an integral door cover that is cast in a special mold that produces a weakened tear seam in the bottom of an aesthetically pleasing groove that does not require any cutting after the skin is cast.
Still another feature and advantage of the invention is that trim panel is cast in a mold that has a raised rib for forming a groove that partially outlines a flap in a cast plastic skin and that includes a tear seam that can be ruptured by a deploying airbag without any need for cutting the tear seam after the plastic skin is cast.
Yet still another feature and advantage of the invention is that it provides a special mold having a uniquely shaped rib for casting a flexible plastic skin so that the cast plastic skin is formed with a groove that partially outlines a flap and that includes a tear seam that can be ruptured by a deploying air bag without any need for cutting the groove.